Impedance-based stability analysis normally splits an interconnected system into source and load subsystems and the stability of the closed loop system can be analyzed by the combined input-output gains of source and load. This is an intuitive approach in the case of Single-Input Single-Output (SISO) systems. However, in the case of grid-tied voltage source converter (VSC) systems, dq impedance...

Protein loops are essential structural elements that influence not only function but also protein stability and folding rates. It was recently reported that shortening a loop in the AcP protein may increase its native state conformational entropy. This effect on the entropy of the folded state can be much larger than the lower entropic penalty of ordering a shorter loop upon folding, and can th...

This paper presents a sequential loop closure approach to designing a velocity and altitude tracking autopilot for a hypersonic vehicle. The control architecture consists of two decoupled control subsystems, one for velocity, the other for altitude. The velocity control subsystem consists of an adaptive augmented baseline controller. The altitude control subsystem consists of an adaptive inner-...

In this paper a new method is introduced and investigated for removing the destabilizing effects of time-delay parameter in control loops. The concept of the method is taken from the knowledge concerning the dynamic behaviour of irrational transfer functions (Ir-TF), which is discussed and investigated elswhere in frequency response domain and is explained briefly here. Ir-TFs, which are we...

Due to the prediction loop, instability is a major difficulty in the design of a predictive quantizer. The conventional open-loop method enjoys good stability but suffers from poor performance. In contrast, the closed-loop method may be able to perform better but it can not guarantee a complete convergence and so it is unstable. Recently, the asymptotic closed-loop approach was proposed to bene...

This paper presents a control methodology that provides transparency and stability robustness in bilateral telemanipulation systems that include a significant time delay in the communication channels. The method utilizes an adaptive Smith predictor to compensate for the time delay, and incorporates a previously published loop shaping approach to design a compensator for transparency and stabili...

The paper deals with the stability analysis of time-delay reset control systems, for which the resetting law is assumed to satisfy a time-dependent condition. A stability analysis of the closed-loop system is performed based on an appropriate sampled-data system. New linear matrix inequality (LMI) conditions are proposed to ensure the exponential stability of the closed-loop resulting of the co...

A hybrid control structure that unites bounded control with model predictive control (MPC) is proposed for the constrained stabilization of nonlinear systems. The structure consists of: (1) a finite-horizon model predictive controller, which can be linear or nonlinear, and with or without stability constraints, (2) a family of bounded nonlinear controllers for which the regions of constrained c...

In this paper, an efficient method is presented to control the attitude of a satellite with ON-OFF actuator. The main objective of this novel method is to control the amplitude of the limit cycle which commonly appears in the steady state of such systems; and at the same time by consideration of real actuator constraints, reduce the fuel consumption of system. The Proposed method is a combinati...

We consider stability and robustness of feedback systems, where plant and compensator need not be strictly proper. In an earlier paper [1] we described a functional R∞ which, when negative, guarantees closed-loop instability as a result of parasitic interactions in the feedback loop. In our main result, Theorem 5, we prove that, when R∞ > 0, there exist perturbations of plant and compensator fr...